XorMon (LPAR2RRD) AIX OS agent can coexist with the Dynatrace OneAgent except AIX 7.3 TL3 and probably even higher.
Dynatrace OneAgent somehow screws something in the AIX environment what leads to this error visible in the agent output (/var/tmp/lpar2rrd-agent.out)
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Thu Sep 17 09:47:01 2026: Model or serial has not been found: model: serial: /opt/lpar2rrd-agent/lpar2rrd-agent.pl:1391
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Workarounds
All worarounds work, up to you which one you use
Dynatrace:
Dynatrace does not know why this is happening under AIX 7.3 TL3, but they found a workaround by adding AIX:"ksh" AIX:"perl" to the agent block list
This setting is not configurable by the end user and can be done only in via developer access interface to Dynatrace and by calling support